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I can't see anything on the report which confirms that my line goes to
the exchange. Perhaps it would mention cabinets if there were a cabinet
involved? At the top it says "telephone number .. on Exchange
...". Perhaps that would be different?

I can't see anything on the report which confirms that my line goes to
the exchange. Perhaps it would mention cabinets if there were a cabinet
involved? At the top it says "telephone number .. on Exchange
..". Perhaps that would be different?

Click to expand...

If it says on Exchange then you are an EO line -
otherwise it says your line is on Cabinet N.

Bad news is that the high voltage pulse sometimes heals an intermittent
fault and you get just a small reflection followed by nothing at all.

Click to expand...

Not always that high. A chap I know designed such a device
for use on the original [thick] Ethernet. The pulse was 1V and>
done in a way to fool all the devices that the net was busy.

Click to expand...

You can check the distance to a short circuit or open circuit along a
75 Ohm co-axial cable using nothing more than an ordinary analogue
video signal and an oscilloscope. The signal is 1V including 0.3V sync
pulses and there is no danger of it healing intermittent faults. You
just need to know how to measure the duration of reflections on the
scope, taking a value of 200 metres per microsecond for the speed.

Can the Roo lead me to my cabinet? I have no idea where it is despite
having walked round the area. The BT map shows it somewhere between the
corner of the street we're on and what cannot be more than 200 yards
along the road.
Bill.

Can the Roo lead me to my cabinet? I have no idea where it is
despite having walked round the area. The BT map shows it somewhere
between the corner of the street we're on and what cannot be more
than 200 yards along the road.

Click to expand...

Question: what maps and where do I find them? I know I am on cabinet 8
but where is it is my problem? Plenty of clearly marked VM cabs but
what there of BT seem to have no marking in the main.

This page is dated 2011. The text begins "BT has created a map showing
which exchanges are in line to be enabled for its fibre-to-the-cabinet
Infinity broadband" but there is no hint as to where, if anywhere, we
can download or even look at the map.

If you want to know where your local BT boxes are, it seems there is
no other way than to do some research yourself. Put a few sample
addresses near you into the DSL speed estimator and see which way the
"speed gradients" go on a map, then have a look around on Google
Street View where the speeds are highest. If you find a box by this
method, make the final check by going to the box in person and looking
at it, because the images on Google can be several years old. The
boxes usually have numbers painted on them.

I don't walk - I use Streetview, although it may not show the fibre cab
too.

Click to expand...

I wondered around my locale on street view, and found a cabinet. There
was a church near by, so I googled its telephone number, then put it
into dslchecker. The church is connected to an exchange via a
cabinit. The exchange is 5 or 6 miles away, even though the church is
nearer to the local exchange that I am connected to than I am. It says
the church can get 80 Mbps.

How has this system come about? Why are some places connected to
cabinets and others directly to the exchange?

I wondered around my locale on street view, and found a cabinet. There
was a church near by, so I googled its telephone number, then put it
into dslchecker. The church is connected to an exchange via a
cabinit. The exchange is 5 or 6 miles away, even though the church is
nearer to the local exchange that I am connected to than I am.

Click to expand...

That'll normally be because when they had a phone installed the nearest
exchange was filled up.

It says the church can get 80 Mbps.

Click to expand...

That'll be using "Infinity".

How has this system come about? Why are some places connected to
cabinets and others directly to the exchange?

Click to expand...

The one connected direct to an exchange are the ones where the cable
length is short enough that the pole it needs to reach is closer to the
exchange than the first cabinet in that general direction.

I wondered around my locale on street view, and found a cabinet. There
was a church near by, so I googled its telephone number, then put it
into dslchecker. The church is connected to an exchange via a
cabinit. The exchange is 5 or 6 miles away, even though the church is
nearer to the local exchange that I am connected to than I am. It says
the church can get 80 Mbps.

How has this system come about? Why are some places connected to
cabinets and others directly to the exchange?

Click to expand...

Lack of coordination, coupled with a universal service obligation and
a very slow rollout.
first there was an exchange, and the dozen or so places that had
phones all connected directly to it.
The number of subscribers grew over time, until (in various locations
and at different times) it became sensible to run a fat cable to a
cabinet, and distribute smaller cables from there. Existing lines
which went direct to the exchange wore not moved to the cabinet
though. Then as cabinets fill up, cables are run from the nearest
cabinet with spare capacity, instead of a full one that's closer. Add
a bit of customer churn, and you get the mess we have now.
Of course, it could be improved, but it would cost a fortune to do so,
and would inevitably interrupt service to some people as their
connections were moved.
It's a bloody miracle it even works for voice, never mind data (which
it was never designed for).
These are the same wires we used to think we were lucky to get 1200/75
baud modems to work over, and now we feel hard done by if we can't get
10,000 times that!

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